The field of the invention relates generally to data gathering systems which may include a scanner for scanning an item and a scale for weighing items.
Data gathering systems which may be installed in checkout counters in supermarkets and other retail locations commonly include a scanner to scan items of food or other products. The scanner typically scans or reads bar codes, industrial symbols, alphanumeric characters or other indicia for object recognition. Typically, bar code labels or other indicia are read as items are passed over a scanning window in the top surface of the scanner. The bar code or other indicia is then converted into product identification and pricing information which may be used for inventory control and to calculate a customer's bill. Certain existing data gathering systems also include a scale which allows the checkout clerk to weigh items which are sold according to weight such as produce. The weight may then be fed directly to the point of sale terminal for purposes of calculating a price.
The scanner component typically includes a light source such as a laser, a rotating mirror driven by a motor, and a mirror array. The laser beam is reflected off the rotating mirror and mirror array to produce a pattern of scanning light beams. As a bar code or other indicia on the item is passed over the aperture or window, the scanning light beams scatter off the bar code or other indicia, and a carrier signal returns to the data gathering system where it is collected and detected. The scale component of such data gathering systems typically comprises a top plate on which the item to be weighed is placed. The top plate may also include an aperture or window whose location corresponds to the window of the scanner and through which the scanning light beams pass.
Certain data gathering systems which include both a scanner and scale arrange these components so that the scanner assembly is mounted on and above the scale assembly. One problem with this configuration is that when an item is weighed, the actual weight detected includes the weight of the scanner assembly. Thus, the weight of the scanner must be "zeroed out" or calibrated so that the weight reading will reflect only the weight of the item. Furthermore, the accuracy and speed of the scale may be affected by weighing the additional scanner mass. Still further, it may be difficult to actually calibrate or zero-out the system in such a configuration. Yet another problem regards the cables used to connect the scanner to the scale. The weight of the cables themselves has been seen to inconsistently contribute to the weight reading. Also, the cables have been seen to periodically rub against other components of the system thereby causing drag and a consequent inaccurate weight reading.
Mounting the scanner on top of the scale also increases the overall vertical dimension of the system which in turn requires that the counter provide a larger volume of space below the countertop for installation. The requirement of increased volume may preclude that a checkout clerk sit down with his or her legs underneath the counter. Furthermore, the counter may simply be unable to accommodate a system with a high vertical dimension regardless of whether a checkout clerk's legs are to be located underneath the counter. Still further, the system's bulk is increased making it significantly more difficult to install and remove from the counter.
In some systems, a scale component is placed alongside the scanner component. However, this side-by-side configuration greatly increases the "footprint" (i.e., length and width) of the system which in turn requires that a larger (or a second) hole be cut out of the countertop to accommodate the larger footprint of the data gathering system.
Certain existing systems require that both scanner and scale assemblies be supported by their own set of electronic components such as printed circuit boards, cables and hardware. Thus, the system effectively has two sets of components, many of which are duplicative between the two assemblies. The increase in number of components increases the chances of failure as well as adds to the system's size and cost.
Another problem synonymous with existing scanner/scale systems is that they may require substantial disassembly for maintenance procedures. For example, where the scanner is mounted on top of the scale, much or all of the scanner may have to be removed so that problems located under the scanner or in other hard to reach locations, may be diagnosed and rectified. Removal of the scanner itself may be difficult in those systems where the scanner does not exhibit a modular design to allow the scanner to be removed as a unit.
Furthermore, merely isolating the area requiring service may require extensive troubleshooting efforts. Existing systems do not include diagnostic readouts or other indicators which can identify the failed component(s) without disassembling the system. Thus, a technician may have to spend substantial time merely isolating the problem, let alone disassembling and repairing it. Even if the malfunction is contained in an easily accessible component, the design of existing data gathering systems may require that a technician remove the component from the system so that test points may be probed to locate the malfunction. Probing test points may require that an oscilloscope or other expensive test equipment be used which may be difficult if the system is to be serviced in the field.
Another problem with existing data gathering systems is that the top of the system, or platter, where items are placed for weighing purposes, may oftentimes contact the countertop. Contact may result from an improperly dimensioned hole in the countertop through which the system is installed. Such contact causes improper vertical deflection of the scale and incorrect weight measurements.
Thus there is a need for a data gathering system which overcomes the problems noted above.